The positive likelihood ratios for IL-6 IL-4, and IL-6/IL-4 in synovial fluid of patients with PJI were 1.90, 11.96 and 71.33, the negative likelihood ratios were 0.17, 0.30, and 0.19, and the DOR were 11.18, 39.87, and 377.52, respectively. This evidence concerns the gene IL4 and juvenile polyposis syndrome.